1. 叨叨

MCP测试SSE模式

来自公众号 十分钟入门MCPServer , 其实用不了十分钟

这次的核心库是 ModelContextProtocol ,就是官方的库

上次的库MCPSharp还没有支持SSE

2. 引用

新建API项目，引用库

  <ItemGroup>
    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.6.2" />
    <PackageReference Include="ModelContextProtocol" Version="0.1.0-preview.2" />
    <PackageReference Include="Flurl" Version="4.0.0" />
    <PackageReference Include="Flurl.Http" Version="4.0.2" />
  </ItemGroup>

3. 核心类 McpEndpointRouteBuilderExtensions

就是开启 /sse

using Microsoft.Extensions.Options;
using ModelContextProtocol.Protocol.Messages;
using ModelContextProtocol.Protocol.Transport;
using ModelContextProtocol.Server;
using ModelContextProtocol.Utils.Json;

namespace WebSSE
{
    public static class McpEndpointRouteBuilderExtensions
    {
        public static IEndpointConventionBuilder MapMcpSse(this IEndpointRouteBuilder endpoints)
        {
            IMcpServer? server = null;
            SseResponseStreamTransport? transport = null;
            var loggerFactory = endpoints.ServiceProvider.GetRequiredService<ILoggerFactory>();
            var mcpServerOptions = endpoints.ServiceProvider.GetRequiredService<IOptions<McpServerOptions>>();

            var routeGroup = endpoints.MapGroup("");

            routeGroup.MapGet("/sse", async (HttpResponse response, CancellationToken requestAborted) =>
            {
                await using var localTransport = transport = new SseResponseStreamTransport(response.Body);
                await using var localServer = server = McpServerFactory.Create(transport, mcpServerOptions.Value, loggerFactory, endpoints.ServiceProvider);

                await localServer.StartAsync(requestAborted);

                response.Headers.ContentType = "text/event-stream";
                response.Headers.CacheControl = "no-cache";

                try
                {
                    await transport.RunAsync(requestAborted);
                }
                catch (OperationCanceledException) when (requestAborted.IsCancellationRequested)
                {
                    // RequestAborted always triggers when the client disconnects before a complete response body is written,
                    // but this is how SSE connections are typically closed.
                }
            });

            routeGroup.MapPost("/message", async context =>
            {
                if (transport is null)
                {
                    await Results.BadRequest("Connect to the /sse endpoint before sending messages.").ExecuteAsync(context);
                    return;
                }

                var message = await context.Request.ReadFromJsonAsync<IJsonRpcMessage>(McpJsonUtilities.DefaultOptions, context.RequestAborted);
                if (message is null)
                {
                    await Results.BadRequest("No message in request body.").ExecuteAsync(context);
                    return;
                }

                await transport.OnMessageReceivedAsync(message, context.RequestAborted);
                context.Response.StatusCode = StatusCodes.Status202Accepted;
                await context.Response.WriteAsync("Accepted");
            });

            return routeGroup;
        }
    }
}

4. 工具类

把之前的工具类放上

using Flurl.Http;
using ModelContextProtocol.Server;
using System.ComponentModel;

namespace WebSSE.Tools
{
    [McpServerToolType]
    public static class ERPCost
    {
        [McpServerTool("get-cost-bycode"), Description("通过物料编号得到核价")]
        public static string GetCostByCode(
           IMcpServer thisServer,
           [Description("物料编号")] string code)
        {
            var response = "http://localhost/api/CRM/GetCostByCode"
                .WithHeader("accept", "*/*")
                .WithHeader("Content-Type", "application/json-patch+json")
                .PostJsonAsync(new
                {
                    GUID = "B02C2304120019",
                    hasCode = "",
                    data = new
                    {
                        CostCode = code,
                    }
                })
                .GetAwaiter().GetResult();

            // 处理响应
            var responseString = response.GetStringAsync().GetAwaiter().GetResult();

            var dis = @"Code	1 表示成功 ，非1表示有错误
Message	""成功"" 或 其他错误消息
MB001	品号
MB002	品名
MB003	规格
MB004	单位
CostUnitCost	当前成本（该物料在该账套的最近核价含税）
HasNoCost	1表示BOM中有价格为0的物料，0表示没有价格为0的物料
";
            return responseString + dis;
        }
    }
}

注意这里的 类的声明McpServerToolType 和 方法声明McpServerTool

5. 注册

注册工具

            builder.Services.AddMcpServer().WithToolsFromAssembly();
            app.MapMcpSse();

启动就行了

这样就可以部署到docker进行远程调用了